Brain apoptosis

Caspase-9 Perinatal lethality Excess brain tissue Defects in brain apoptosis, defects in cell death in response to UV or 7 irradiation Normal [67, 68]... 

ALG-2 is the fust calcium-binding protein of the EF-hand family found to be directly involved in apoptosis. ALG-2 is a 22 kDa protein and like the other members of the penta EF-hand family, contains five EF-hands, with only two of them functional. ALG-2 protein is expressed in the brain and eye and was found to be upregulated in various cancer tissues. Several targets have been found, such as proteins AEP, Alix, preflin, and annexins, suggesting a putative role of ALG-2 in apoptosis. 

Acute over-activation of NHE1 results in a marked elevation in intracellular sodium concentration with a subsequent increase in intracellular calcium, via the Na +/Ca++ exchanger. This in turn triggers a cascade of injurious events that can culminate in tissue dysfunction and ultimately apoptosis and necrosis. This is commonly seen in organs such as the heart, brain and kidneys as a consequence of ischemia-reperfusion. 

Muscarinic receptor Brain binding Dopaminergic receptor binding Intracellular Ca concentration, apoptosis Cytosolic phospholipase A2 expression arachadonic acid release... 

The lack of zinc can also be a problem in biological systems and is responsible for disease states. For example, nitric oxide-dependent apoptosis can be induced in motor neurons by zinc-deficient SOD, and in some cases of amyotrophic lateral sclerosis, zinc-deficient SOD may participate in this type of oxidative mechanism involving nitric oxide.969 One form of hereditary human hair loss or alopecia was mapped to a specific gene and a mutation found in affected individuals. The gene encodes a single zinc finger transcription factor protein with restricted expression in the brain and skin.970 Zinc has been implicated in Alzheimer s via beta amyloid formation, and a role has been attributed for the cerebral zinc metabolism in the neuropathogenesis of Alzheimer s disease.971... 

In summary, it appears that the apoptosis pathway can be regulated at various levels (the aforementionned description is far from being exhaustive), while many proteins and cell systems involved in this regulation remain to be discovered. Whereas the cascade of intracellular events implicated in experimentally-induced apoptosis has become more and more elucidated, it is worth noting that only few direct evidences arguing for the presence of an actual apoptosis in the brain of pa-... 

Classic antioxidants, vitamin E, vitamin C, and others can suppress the activation of apoptosis. For example, ascorbic acid prevented cytochrome c release and caspase activation in human leukemia cells exposed to hydrogen peroxide [128], Pretreatment with A -acctylcystcinc, ascorbate, and vitamin E decreased homocysteine thiolactone-induced apoptosis in human promyelocytic leukemia HL-60 cells [129]. Resveratrol protected rat brain mitochondria from anoxia-reoxygenation damage by the inhibition of cytochrome c release and the reduction of superoxide production [130]. However, it should be mentioned that the proapoptotic effect of ascorbate, gallic acid, or epigallocatechin gallate has been shown in the same human promyelocytic leukemia cells [131]. 

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